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9 



ROfAt 



TRANS ACTIO 
OF THE 




.iliicaSOCIETY OF TROPICAL MEDICINE 
AND HYGIENE 



/// 



MARCH, I 9 I O 
VOLUME III. NO. 5 




LONDON: 
SOCIETY OF TROPICAL MEDICINE AND HYGIENE 

II CHANDOS STREET, CAVENDISH SQU.\RE, \V. 



TRANSACTIONS 

« 
OF THE 

SOCIETY OF TROPICAL MEDICINE 
AND HYGIENE. 



MARCH, 1910. 
Volume III. No. 5. 



Proceedings of a Meeting of the Society, on Friday, 
February 18th, 1910. 

Professor RONALD ROSS, C.B., F.R.S., President, 
in the Chair. 



SOME DIPTEROUS INSECTS WHICH CAUSE 
MYIASIS IN MAN. 

BY 

ERNEST E. AUSTEN, F.Z.S., 

British Museum (Natural History). 



It is probably unnecessary to remind any Fellow of a 
Society which has the honour of having our distinguished 
President at its head, that the principal manner in which 
Diptera, or Two-Winged Flies, cause disease among 
human beings is by the inoculation, by certain blood- 
sucking species,' of pathogenic micro-organisms, which 
enter the human body from the insect's proboscis when 



216 SOME DIPTEROUS INSECTS WHICH 

the fly inflicts its bite. Fortunately for the human race, 
however, the blood-sucking habit is highly exceptional 
among Diptera, since the vast majority of species belong- 
ing to this ubiquitous Order of insects possess mouth- 
parts of a type which does not enable them to pierce 
the skin of a vertebrate. Yet, in addition to the 
aggressive disease-disseminators, as we may term the 
carriers of malaria, yellow-fever, dengue, Phlebotomus — 
or three-day fever, filariasis, and sleeping sickness, it is 
now recognised that under certain circumstances other 
Diptera play a considerable part in the dissemination of 
cholera and enteric fever, and possibly other diseases, 
such as summer diarrhoea in England and framboesia or 
yaws in the West Indies. The insects concerned in these 
cases, which are chiefly the house-fly and certain allied 
species, are incapable of sucking blood, and may be 
designated passive disease carriers, since the specific 
disease-germs are mechanically conveyed by them, either 
on the exterior of their feet or bodies or in their dejecta, 
to food or drink, the lips of healthy individuals, or to 
lesions in the skin, as the case may be. 

In both of the groups of diseases to which I have just 
alluded the insect, whether mosquito, sand-fly, tsetse or 
house-fly, is merely the vehicle, and does not itself cause 
the malady. There remains yet a third category of flies, 
chiefly belonging to the great Family Muscidae, the larval 
stage of which is sometimes actually passed in the living 
human body, the presence of the larvae in various organs 
and tissues, and the disorders or destruction of tissue 
caused thereby being comprehensively known as Myiasis. 
It is to certain of the^e flies that I wish to direct your 
attention to-night, and so far as possible I shall restrict 
myself to species which, in the course of my work at the 



CAUSE MYIASIS IN MAN. 217 

British Museum, have been submitted to me for deter- 
mination by medical men and others in various parts 
of the Tropics. Since I have not the honour of belonging 
to the medical profession, it is perhaps unnecessary to 
remark that 1 am not concerned with remedies or 
methods of treatment, the subject of this paper being 
the insects themselves. 

Myiasis is a phenomenon vv^hich affects not only 
human beings but also very many of the lower animals, 
including mammals, both domestic and wild, birds, fishes, 
and batrachians. While it would here be out of place 
for me to deal with any but human parasites, it may be 
of some interest to point out a fundamental difference 
which distinguishes the vast majority of cases of human 
Myiasis from most of the instances met with in other 
mammals. Generally speaking, although exceptions 
occur, when Dipterous larvae are found in living 
' mammals other than man they are those of OEstridae 
Coften known as " bots " or "warbles"), of which 
(Estruft ovis, Linn, (the nose bot-fly of the sheep), 
Gastrophilus equi, Clark (the bot-fly of the horse), and 
Hypoderma lineatum, Vill. (the common warble-fly of 
cattle in England), are familiar examples. Now these 
flies and many others belonging to the same Family 
which similarly infest wild mammals (chiefly ungulates 
and rodents), are in the larval stage invariably parasitic 
in the bodies of their hosts ; they have no alternative 
mode of development, and a female bot- or warble-fly 
deprived of access to a mammal would be as incapable of 
perpetuating its species as a mosquito in the Sahara, a 
hundred miles from the nearest oasis or water-hole. 
While, as I hope to show later on, CEstrid larvae occa- 
sionally infest man, such cases, although comparatively 



218 SOME DIPTEROUS INSECTS WHICH 

often recorded, are nevertheless exceptional, most 
instances of Myiasis in the human subject being due to 
larvae which are not habitual parasites, but are more 
usually found living and feeding in dead or decaying 
animal or vegetable matter, or in excrement. 

As a rule Myiasis 'occurs either in the nasal passages 
and frontal sinuses, the external auditory meatus, the 
alimentary canal, or the subcutaneous tissue of one or 
other of the extremities, in the latter case the parent fly 
having in some instances deposited its eggs or larvae in a 
wound or other lesion of the skin. The finding of maggots 
in the wounds of soldiers was a common experience of 
surgeons in the Crimean War, and there can be no 
doubt that the occurrence of Myiasis in the nasal fossae 
and also in wounds and ulcers on the extremities is . due 
to an aberration of instinct on the part of the parent fly, 
the insects having been lead astray by odours which, 
though repulsive to the human nostril, possess an over- 
powering attraction to certain flies. An analogous 
exhibition of perverted instinct has been observed in the 
case of Calliphora vomitoria, the country cousin of the 
familiar blow-fly or blue-bottle (C. erythrscephala), 
which has been known to oviposit on Arum dracunculus, 
being deceived by the corpse-like odour of the plant ; 
while in Trinidad, B.W.I., it was found some years ago 
that the screw-worm fly {Chrysomyia macellaria) is 
attracted by the carrion-like odour of Aristolochia gigas, 
var. sturtevanti. Intestinal Myiasis, on the other hand, 
is probably caused in very many cases by the swallowing 
of the eggs or living larvae in uncooked food, while 
occasionally, as in the case of intestinal Myiasis produced 
by the larvae of species of Sarcophaga, which are 
viviparous, a pregnant living fly may have inadvertently 



CAUSE ^fYIASIS IN MAN. 219 

been swallowed. In this country, as also in America, 
intestinal Myiasis is perhaps most frequently produced 
by the peculiarly unpleasant-looking larvae of Homa- 
lomyia (or as it now called Fannia) canicularis, a 
fly which is common in houses, somewhat resembles a 
diminutive house-fly, and consequently is sometimes 
ignorantly supposed to be a "young" specimen of its 
larger relative : in this case there seems reason to believe 
that the maggots make their way into the intestine 
through its terminal orifice. There remains a fifth kind 
of Myiasis, also often caused by the larvae of the last 
mentioned fly and occasionally met with by medical 
practitioners in England, on the Continent, and in the 
United States. I refer to Myiasis of the urinary 
passages, but to this, although in some respects the most 
interesting of all, I now merely make passing reference, 
since in the present paper I wish to devote myself more 
especially to Tropical Myiasis, and as yet no cases of this 
particular form of the malady have been brought to my 
knowledge from the Tropics. Those who desire to learn 
more of this branch of the subject should refer to the 
elaborate paper published last year by Chevrel (Ren^ 
Chevrel : " Sur la Myase des Voies Urinaires ; " Archives 
de Parasitologie, T.XII., No. 3, Febr. 10, 1909, pp. 369 
— 450 : figs, in text). 

As I have already stated, the majority of flies causing 
Myiasis in man belong to the great Family Muscidae, 
which, in its wider sense, is by far the largest of all the 
Families of Diptera, and includes not only the house-fly 
{Musca damestica, Linn.) and its near relations such as 
the blow-flies (Calliphora) , green-bottles {Lucilia), the 
genus Pycnosoma, of Africa and the Oriental Region, and 
the screw- worm flies {Chrysomyia) of the New World, 



220 SOME DIPTEROUS INSECTS WHICH 

but also the grey flesh-flies (Sarcophaga) , the tsetse-flies 
{Glossina), Stomoxys, and an almost infinite number of 
species belonging to innumerable other genera. All of 
these flies, as their family name implies, exhibit a 
general resemblance to the house-fly in outward form 
and in the details of their external structure, and they 
breed, as a rule, in decaying organic matter or in 
excrement. While the majority lay eggs, the very 
numerous species of the universally distributed genus 
Sarcophaga produce living larvae, and in any case (except 
in Homalomyia) the footless larvse are whitish or 
yellowish grubs of the type commonly known as maggots. 
A Muscid maggot, which consists of twelve visible 
segments, is broader posteriorly and tapers to the 
cephalic extremity, from which the tips of the two 
powerful chitinous mouth-hooks, with which the creature 
rasps away its food, can usually be seen protuding. The 
main respiratory apertures, which are situate on the 
flattened or cup-shaped posterior surface of the terminal 
segment, consist of two groups of three slits, each group 
being surrounded by a chitinous plate, and there are two 
subordinate groups of apertures, or stigmata, on the first 
postcephalic segment. Larval life, in the Tropics at any 
rate, is usually short, generally lasting no longer than 
from four to six days, and at its conclusion the maggot 
contracts, and its skin hardens and darkens, assuming, as 
a rule, first a reddish and subsequently a reddish-brown 
hue, and forming a protective case or puparium within 
which the pupal or chrysalis stage is assumed. About a 
fortnight later the perfect fly makes its appearance, 
emerging through an aperture in the anterior end of the 
puparium, which the insect forms by forcing off a cap by 
means of pressure exerted by a dilatable vesicle in its 



CAUSE MYIASIS IN MAN. 221 

head. Under normal conditions the pupal stage of all 
Muscidse is passed in the ground, so that, in a case of 
Myiasis, the larvae, if allowed to remain undisturbed, 
would naturally leave their host on attaining maturity. 

Apart from those caused by larvae of Muscidae and 
(Estridae, the only cases of tropical Myiasis with which I 
am at present acquainted have been due to Phoridae, a 
remarkable Family of extremely small flies, of a hunch- 
backed appearance, and usually dusky colour, characterised 
by a peculiar arrangement of the wing-veins and with 
very varied life histories, though many species normally 
breed in decaying vegetables. Two instances of Myiasis 
produced by a species belonging to this Family, in the one 
case in the eastern, the other in the western hemisphere, 
will be referred to later. In Europe, at any rate, 
intestinal Myiasis is occasionally caused by larvae of 
species which one would certainly not expect to find in th* 
human alimentary canal. Thus, during some four weeks 
in the autumn of 1907 a number of larvae of the common 
drone-fly, Eristalis te)iax,ljmn. (Family Syrphidae), were 
passed per rectum by a woman in Hampshire, who had 
recently arrived from France. These larvae were forwarded 
for identification by Dr. H. McQuade, Eling Lodge, 
Totton, Hants, to Mr. S. G. Shattock, Royal College of 
Surgeons, by whom they were submitted to me. The larvae 
of the drone-fly and allied species (commonly known as 
"rat-tailed maggots") are found in foul water, and since the 
patient in this case had, before leaving France, consumed 
a considerable quantity of watercress, the explanation of 
the presence of the larvae in her intestine was not far to 
seek. Nasal and intestinal Myiasis due to larvte of the 
cheese-maggot fly {Piophila easel, Linn.) are obviously 
capable of similar explanation ; a number of such cases of 



222 SOME DIPTEROUS INSECTS WHICH 

Myiasis occasioned by the larvae of this particular fly are 
recorded in medical literature, and in November last flies 
and puparia of this species from larvae passed from the 
human bowel were sent to me from Lisbon by Dr. Costa- 
Ferreira. 

The literature of Myiasis is very extensive, dating 
back, as it does, for several hundred years, or, at least, 
to the time of Ambroise Par6, who, according to Mr. J. 
Foster Palmer, first described Myiasis of the urethra in 
in 1582 : not to speak of the death of Herod, the king, who, 
as we know, was "eaten of worms" in A.D. 42. Those 
who are interested in the subject will find a most valuable 
summary in the " Bibliography " published eleven years 
ago by HuBER [" Bibliographic der klinischen Ento- 
mologie (Hexapoden, Acarinen)." By Med. -Bath. Dr. 
J. Ch. Huber, K Landgerichtsarzt zu Memmingen. 
Heft 3, Diptera. 8vo. Jena : Druck der Fromman- 
schen Buchdruckerei (Hermann Pohle), Grossherzoglich 
Sachsische Hofbuchdruckerei. 1899. Pp. 25]. The 
greater number of cases recorded in this work, however, 
occurred in non-tropical countries ; and although within 
the last few years many highly interesting notes and 
descriptions of tropical Myiasis have appeared in the 
medical journals, the student of tropical medicine will 
find it difficidt to learn anything as to the names and 
characteristics of the Myiasis-producers most likely to 
be met with in the particular part of the globe in which 
his future lot may be cast. In the volume on " Tropical 
Diseases and Animal Parasites," in the last edition of 
Allbutt's and Rolleston's System of Medicine, less 
than a page and a half are devoted to the subject, and even 
within this short space there are several inaccuracies 
and misstatements. It is therefore not in any way 



CAUSE MYIASIS IN MAN. 223 

surprising that the contributors of notes on Myiasis 
sometimes err, when they attempt to assign generic 
and specific names to the parasites that they have 
observed. Under the circumstances, I may perhaps be 
forgiven if I venture to suggest that in such cases it 
is better not to apply definite names to genera and 
species, unless the designations have been duly verified, 
aince the contrary course may lead to errors which 
eventually find their way into text-books. 
' Having said so much by way of introduction, I will 
now refer to a few of the principal genera and species 
of Diptera which cause Myiasis in different parts of 
the Tropics; and. though, from the zoological standpoint, 
it would be more scientific to consider the genera and 
species concerned in proper systematic sequence, from 
a practical point of view it will probably be more con- 
venient if I follow a geographical arrangement. I will, 
therefore, deal in turn with Africa, Asia, and Tropical 
America (including the West Indies). Up to the present, 
no cases' of Myiasis have come to my knowledge from 
Tropical, or indeed any part of Australia. 

AFRICA. 

Cordylobia anthropophaga, Grilnh. — This insect, which 
is very widely distributed in Africa, its range extending 
from Senegal to Natal, belongs to the same group of the 
Family Muscidse as does the European blow-fly {Calli- 
phora erythrocephala, Mg.), to which it is nearly allied. 
In appearance it is thick-set and compactly built ; its 
general coloration is straw-yellow, with blackish mark- 
ings on the dorsum of the thorax and abdomen, and its 
average length is about 9.5 mm. The full-grown larva 
is a fat yellowish-white maggot, 12 to 12.5 mm. (about 



224 SOME DIPTEROUS INSECTS WHICH 

half an inch) in length, bluntly pointed at the anterior 
extremity, and truncate behind ; its greatest breadth 
(on the sixth and seventh segments) is 5 mm. The body 
of the larva, from the third to the eleventh segment, is 
thickly covered with minute recurved spines of brownish 
chitin (darker in the ' case of larvae ready to leave the 
host), usually arranged in transverse series of groups of 
two or more, which can be seen to form more or less 
distinct, undulating or irregular, transverse rows. In 
each of the two posterior stigmatic plates, the respiratory 
slit on either side of the median one is characteristically 
curved, resembling an inverted note of interrogation. 
The barrel-shaped puparium is on an average 10.3 mm. 
in length, by 4.6 mm. in breadth ; its colour varies 
according to age from ferruginous to nearly black. 

Cordylobia authropophaga, which in Sierra Leone is 
known as the Tumbu- or Tumba-fly, forms a remarkable 
exception to the general rule that, exclusive of those 
belonging to the (Estridae, the larvae of Diptera that 
cause Myiasis in man are not normally parasitic, since, 
so far as is known at present, the larvae of this inse(j^ are 
met with only in the tissues of a living host. Tumbu-fly 
larvae are subcutaneous parasites in human beings (both 
Europeans and natives) , monkeys, dogs, rats and probably 
other mammals. Each larva lives singly, forming a 
boil-like swelling in the skin, which always includes an 
aperture through which it breathes, the opening also 
forming a means of exit for the grub when the latter 
reaches maturity. While it frequently happens that 
only one maggot is found in an individual, the number 
is sometimes much greater, and Mr, G. A. K. Marshall 
records that in Salisbury, Southern ^Rhodesia, in 1901, 
no fewer than sixty of these maggots were extracted 



CAUSE MYIASIS IN MAN. 225 

from a single unfortunate baby. In Senegal, where the 
larva is known as the " Ver de Cayor," according to M. 
B^renger-Feraud dogs have suffered to an even greater 
extent, and the author in question tells us that on one 
occasion he counted more than three hundred larvae in a 
single spaniel puppy ; in this case it is not surprising to 
learn that the results were fatal ! We do not yet know 
whether Cordylohia lays eggs or "is viviparous, nor is it 
certain how the larvae reach the parts of the body in 
which they are sometimes found. In any case, since 
{yace the author of the paragraphs on Myiasis in Allbutt 
& Rolleston) the ovipositor of the female fly is quite 
incapable of piercing the skin, the young larva must bore 
its own way through the integument by aid of its mouth- 
hooks. 

It should be noted that within the last few years 
Cordylohia anthropophaga has been wrongly identified as 
Bengalia depressa, Walk., under which name it has 
frequently been referred to in literature ; the true B. de- 
pressa, however, is a very different insect, the life-history 
of which is unknown, and there is no evidence whatever 
to show that its larva is a subcutaneous parasite.^ 

Sarcophaga. — As has already been remarked, the vi- 
viparous or rather larviparous genus Sarcophaga is very 
numerous in species and universally distributed. The 
members of this genus, which are flies of usually con- 

1. Cf. E. E. Austen, Proceedings of the Entomological Society of 
Lo7idon for the Year 1907, p. xlvii. For a detailed description and 
figures of the larva and perfect insect of Cordylohia anthropophaga , 
cf. E. E. Austen, "The Tumbu-Fly (Cordylohia anthropophaga, 
GRiJNBERG) " : Journal of the Royal Army Medical Corps. 1908. 
pp. 5-11, Figs. 1 and 2. See also Major F. Smith, D.S.O., R.A.M.C. 
"Tumbu-Fly Disease in Sierra Leone"; ibid., pp. 1-2: and Major 
A. P. Blenkinsop, R.A.M.C, "Observations on Tumbu-Fly Disease;" 
iMd., pp. 3-4. 



226 SOME DIPTEEOUS INSECTS WHICH 

siderable or at any rate moderate size, are remarkably 
uniform in appearance, and resemble one another so 
closely that the species are exceedingly difficult to 
distinguish. Comparatively few of these species, in 
proportion to the total number in existence, have yet 
been described and named, and, since most of the 
recognisable distinctive characters are confined to the 
male sex, it is generally impossible to determine solitary 
females. In coloration the species of Sarcophaga are 
grey, with dark lines on the dorsum of the thorax, and 
characteristic, shimmering, chequered markings on the 
abdomen. Although these flies normally breed in carrion 
of all kinds, or in excrement, a large amount of Myiasis 
in man — chiefly nasal and cutaneous, but sometimes 
intestinal — is caused by their larvae. A number of such 
cases have been recorded in Europe and the United 
States, though there is reason to believe that the 
majority of the European attacks are due to larv8B 
belonging to the closely allied genus Wohlfahrtia, in the 
perfect insects of which the light grey abdomen bears 
shining black spots, which do not change their shape and 
appearance according to the angle from which the fly is 
viewed. In South Russia, the large and handsome 
Wohlfahrtia magnifica, Schin. (syn. Sflrcophila wohlfahrti, 
Portch.) is responsible every year for very many cases of 
cutaneous Myiasis in man and domestic animals, cattle, 
horses, pigs, sheep, dogs, and geese, besides human 
beings suffering from the attacks of the larvsB. 

Sarcophaga {species incerta). — Although I am unable 
to record any actual cases of cutaneous Myiasis due to' 
African species of Sarcophaga, the following instance 
of suspicious behaviour on the part of one of these flies 
is perhaps worthy of mention. At Zomba, in April, 



CAUSE MYIASIS IN MAN. 227 

1907, Sir Alfred Sharpe, K.C.M.G., C.B., Governor 
and Commander-in-Chief of the Nyasaland Protectorate, 
crushed a female Sarcophaga inside his sleeve. The fly 
was forwarded to me by Major F. B. Pearce, C.M.G., 
Deputy-Governor, with the following note, dated Zomba, 
April 12th, 1907 : — "On Sir Alfred Sharpe shaking his 
arm the fly fell out. Some thirty small white maggots 
were issuing in every direction from the crushed fly's 
body, and it can only be presumed that the insect crept 
up Sir Alfred's sleeve for the purpose of depositing 
one or more of these maggots in {i.e., on) his arm. 
They were very much alive as they came out of their 
mother's body." Dried specimens of the young larvae, 
sent by Major Pearce with the fly, are l'5mm. in 
length, and under low magnification show dark trans- 
verse bands formed by minute spines. The fly itself is 
11mm. in length, and, as in the vast majority of African 
species of Sarcophaga, its anal segments are orange- or 
ochraceous-rufous. Owing to the sex, not to speak of 
the sadly battered condition of the specimen, the species 
cannot be determined. 

Writing in the Jaumal of Tropical Medicine for 
November 15th, 1905, p. 327, Dr. F. Creighton Well- 
man stated that in Angola he had brought about experi- 
mental Myiasis in a goat by means of an undetermined 
species of Sarcophaga. " The animal," wrote Dr. 
Wellman, " was tied under a mosquito curtain in such 
manner that it could not move its head, and the flies 
liberated under the curtain. The larvae were deposited 
in the nostrils, and produced erosions and necrosis." 

Some four years ago, Mr. E. Warren, of the Govern- 
ment Museum, Pietermaritzburg, forwarded to the 
British Museum (Natural History) an adult Sarcophaga, 



228 SOME DIPTEKOUS INSECTS WHICH 

which was stated to have been bred from a larva passed 
ahve with " scores " of others from the intestine of a 
white girl in Natal. This fly, which is apparently nearly 
allied to S. regularis, Wied., although, being unfor- 
tunately a female, it is impossible to be certain as to 
its specific identity, is 11mm. in length, and, like the 
specimen killed by Sir Alfred Sharpe, has the terminal 
segments of the abdomen ochraceous-rufous. 

According to Dr. Creighton Wellman, Myiasis, both 
intestinal and cutaneous, is not infrequent in Bih^, 
Angola, and this careful observer has described an 
intestinal case treated by him in that country, which 
was caused by larvae of "Anthomyia desjardensii, Macq.," 
a species allied to Homalomyia {cf. F. Creighton 
Wellman, M.D., " Intestinal Myiasis in Angola," The 
Journal of Tropical Medicine and Hygiene, Vol. X., 
No. 11, June 1st., 1907, p. 186). 

CEstris ovifi, Linn. — In Algeria, according to Drs. 
Edmond and I^tienne Sergent (Annales de I'lnstitut 
Pasteur, T. XXI., 1907, p. 392), the sheep bot-fly, 
(Estrus ovis, Linn., is responsible for a form of Myiasis 
among human beings, locally known as Thim'ni. The 
fly is said frequently to attack Kabyl shepherds, laying 
its eggs while flying in the eyes, nostrils and lips; the 
larvae, when hatched, cause intense irritation of the 
conjunctiva, and of the cavities and sinuses of the nose 
and throat. Cases last about twelve days. The authors 
referred to consider that these attacks are probably due 
to the number of sheep being small, while the human 
population is fairly dense ; cases are rare when sheep 
are numerous and human beings few and far between. 



CAUSE MYIASIS IN MAN. 229 

ASIA. 

Aphiochceta ferruginea, Brun. — Passing now from 
Africa to the East, we will first consider a species which, 
though of extremely small size, is of remarkable interest, 
since there seems reason to believe that it is capable of 
passing through its entire life-cycle in the human colon. 
Aphiochceta ferruginea, Brun., which belongs to the 
Family Phoridae, measures some 2 to 3 mm. in length, 
and is of an orange-ochraceous colour, with the dorsum 
of the thorax tawny, dark brown bands on the upper 
surface of the abdomen, and pale yellow legs, which, in 
the case of the hindmost pair have the femora tipped 
with brown. The British Museum possesses a very young 
pupa of this species which has apparently only just passed 
beyond the larval stage. This pupa is 3'5 mm. in length 
by 1*5 mm. in greatest width, buff-coloured (at least, 
after being preserved in spirit), and of the " boat " shape 
charact;eristic of pupae belonging to this family, so that it 
looks like a small seed. It is convex above and 
below, and has a thickened rim runnmg along each side. 
The anterior extremity, the upper surface of which is 
somewhat flattened, is at first tapering, then abruptly 
truncate ; viewed from above, the posterior extremity is 
shaped like one end of an elliptical ovate figure, with a 
row of small spines round its edge. A little in front of 
the hinder margin, the posterior larval stigmata (respir- 
atory apertures) can be seen in the form of two small 
brownish papillae, situate close together ; the prominent 
pupal breathing tubes, that will subsequently make their 
appearance near" the anterior extremity, are not yet 
visible. Finally, it may be noted that an examination of 
this pupa shows that on the upper surface, the majority 
of the larval segments are each encircled by a single row 
of minute and rather widely separated spines. 



230 SOME DIPTEROUS INSECTS WHICH 

It is evident that Aphiochceta ferruginea is very widely 
distributed in the Tropics, since the British Museum 
possesses examples of it from India, Burma, West Afri^ca, 
and Central America ; indeed, the species exhibits so 
remarkable an adaptability to varying conditions, that 
there can be little doubt that it has been introduced into 
fresh localities by human agency. Thus it may be men- 
tioned that in February, 1892, A. ferruginea was found in 
London swarming in a box of live scorpions just arrived 
from Madras. The scorpions were packed in horse-dung, 
and some of the flies which were presented to the 
Museum were accompanied by the statement that the 
donor had seen the insect, or one looking exactly like it, 
swarming over decaying animal and vegetable matter in 
Madras. Typical examples of this fly recently received 
from India were bred, in the Indian Museum, Calcutta, 
from a decaying water-beetle {Cyhister limbatus, Fabr.) ; 
and in Sierra Leone, in November, 1904, the species 
was obtained by Major F. Smith, D.S.O., E.A.M.C., 
from larvae feeding in putrid meat. At Belize, British 
Hond\iras, where, as I am informed by Dr. Karl 
Heusner, the species is plentiful round mangrove roots 
and displays a partiality for for decomposing shell-fish, 
Dr. Heusner bred it, in 1906, from larvas, sixty-three in 
all, extracted by him from an Indian's foot. 

In the Proceedings of the Burma Branch of the 
British Medical Association for 1891, pp. 11 — 16, will 
be found a paper by Surgeon-Major Oswald Baker, 
I, M.S., entitled "The passage from the human intestines 
of swarms of maggots and an explanation of the source 
from which they are derived." The maggots in question 
were passed per anum by a European at intervals during 
some ten months, and Surgeon-Major Baker, who 



CAUSE MYIASIS IN MAN. 231 

attended the case, was satisfied that the trouble originally 
arose through the patient having consumed large 
quantities of candied bael fruit {JEgle marmelos, Correa), 
which on being examined was found to contain maggots 
of the same kind. Two of the flies bred from some of 
the maggots passed from the intestine were forwarded to 
me for identification, but it was only during the prepa- 
ration of this paper that I have discovered the name of 
the species, a comparison with co-types received last 
month from Calcutta having proved beyond doubt that 
they are specimens of Aphiochceta ferruginea, Brun. By 
rearing the insects from the egg, Surgeon-Major Baxer 
found that when the larvae were fed on human faeces, the 
entire life-cycle, from the hatching of one batch of eggs 
to the deposition of eggs by the resultant brood of 
flies, occupied 22 days. On the evidence adduced by 
Surgeon-Major Baker, which can be consulted by those 
who are sufficiently interested, it appears to me that he 
is fairly justified in his conclusion {op. cit., p. 15) that 
" these insects are capable of propagating, and do 
propagate their kind while sojourning within the human 
intestines." Since the consumption of the bael fruit, it 
is stated that the patient ate nothing which could have 
contained either eggs or larvae, yet both newly-hatched 
and fully-grown maggots continued to be passed about 
every two months for nearly a year, while on one 
occasion, according to the patient's own statement (op. 
cit., p. 28), "8 to 12 flies" were passed, "as well as a 
goodly number of maggots." In the same part of the 
" Proceedings of the Burma Branch of the British 
Medical Association " (pp. 28, 29), Surgeon-Major 
Baker records the occurrence of larvae of this fly in the 
intestines of two Karen girls, who were brought to the 



232 SOME DIPTEROUS INSECTS WHICH 

General Hospital, Eangoon, suffering from what was 
considered to be Beri-Beri. It is obvious that it would 
be of much interest, and possibly of some importance, 
if the ability of AphiochcBta ferruginea to pass through 
its entire life-cycle in the human bowel were tested by 
properly controlled experiments on animals. May I, 
therefore, be permitted to express the hope that some of 
those present, who may be returning to the East, will 
take the hint, and subsequently communicate their 
results to the Society ? It seems to me that there is 
nothing inherently impossible. in Surgeon-Major Baker's 
conclusion, and, as showing the adaptability of Phoridae 
to existence under abnormal conditions, it may be 
mentioned that species belonging to this Family are 
among the insects that have been found alive in corpses 
exhumed after being buried for two years. In one 
instance at La Fayette, Indiana, U.S.A., hving larvae, 
pupae, and imagines (perfect flies) of a species believed to 
belong to Conicera — a genus nearly allied to Ajphiochceta 
— were found in numbers in a corpse on exhumation 
after the period mentioned. 

Sarcophaga (species incerta). — In a recent issue of The 
Indian Medical Gazette (Vol. XLIV., No. 10, Oct., 1909), 
Dr. R. Lloyd Patterson, late Medical Officer of the 
Empire of India and Ceylon Tea Co., Ltd., gave, under 
the title of " An Indian Screw-Worm," an illustrated 
account of a truly terrible and fatal case of nasal Myiasis 
in a coolie woman on the Borjuli Tea Estate, Tezpur, 
Assam. The victim was admitted to hospital suffering 
from various disorders on May 28th, and maggots were 
first removed (by douching) on June 6th, when 10 larvae 
were brought away ; on the following day " upwards of 
50 " larvae were expelled, and 100 were removed on 



CAUSE MYIASIS IN MAN. 233 

June 8th, after which none were seen until June 12th, 
when 70 maggots were got rid of. On June 13th, the 
left orbital cavity was found " packed with hundreds of 
the maggots," and we are told that from June 16th to 
the 28th, when the patient's sufferings were mercifully 
terminated by death, from 50 to 70 larvae were removed 
daily. It is, therefore, evident that during the course of 
the case there must have been constant re-invasion by 
fresh broods of maggots, and it is quite possible that 
these may have belonged to more than one species. 
Although Dr. Patterson does not state that he actually 
bred out flies from any of the larvae removed by him, he 
speaks of " green-bottles " being associated with the case, 
and this designation and the description that he gives of 
the fly evidently refer to a species of Pycnosoma, a genus 
which, as I shall show directly, certainly causes nasal 
Myiasis in India. According to Dr. Patterson, in 
Assam the larvae of "green-bottles" (i.e., Pycnosoma) 
" are frequently present in the sores of cattle and more 
rarely in dogs and cats." The figures, however, of the 
maggot concerned in this case, which are given in the 
plate attached to Dr. Patterson's article, show the 
larvae of a species of Sarcophaga ; and five larvse from 
the case, which Dr. Patterson kindly sent me in 
response to my application for specimens, belong to the 
same genus. Dr. Paterson describes the larva as 
" 16 mm. long and 3 mm. broad at it widest part " ;^ the 
maggots received by me, which are of different ages, are 



1. The reader of Dr. Patterson's description should note that 
the author mistakes the head of the larva for its posterior extremity, 
and that in speaking of " a powerful circular sucker " provided with 
certain organs, lie is referring to the depression on the terminal 
segment and to the posterior stigmata contained therein. 



234 SOME DIPTEROUS INSECTS WHICH 

somewhat smaller, measuring from 8'25 to 13 mm. in 
length. 

Although no other instances of Myiasis in any part of 
the East due to species of Sarcophaga have as yet come 
to my knowledge, in India according to Moniez (" Traits 
de Parasitologie," p. 600), who quotes from Kailliet, 
English medical men have reported very serious cutaneous 
Myiasis due to larvae of Sarcophaga ruficornis, Fabr. 
The flies of this species, of which the British Museum 
(Natural History) possesses specimens from India and 
Siam, are generally about 12 mm. or half an inch in 
length and of a light grey colour, with the usual blackish 
markings not so dark as is often the case in this genus, 
while the antennae and palpi are ochraceous-rufous, and 
the anal segments of the abdomen ferruginous. 

PycTwsoma {species incerta). — The metallic blue, green, 
or purple flies belonging to the genus upon which Brauer 
and von Bergenstamm bestowed the name Pycnosoma 
are the Oriental and Ethiopian representatives of 
Chrysomyia, a genus which is confined to the New World 
and includes the well - known Screw -Worm Fly {Ch. 
macellaria, Fabr.). In spite of the statement by the 
writer on Myiasis in Allbutt's & Eolleston's " System," 
the latter species does not occur in the Oriental Region, 
nor, indeed, anywhere outside America (North, South and 
Central) , and the West Indies ; and although the genus 
Pycnosoma is in the latest catalogue of Diptera ("Katalog 
der Palaarktischen Dipteren," Bd. III., by Dr. M. Bezzi 
and P. Stein : Budapest, 1907, p. 543) regarded as 
synonymous with Chrysomyia, Rob.-Desv., there can be 
no doubt that it is really distinct. Pycnosoma can 
readily be distinguished from Chrysomyia by the absence 
of the thriee longitudinal dark stripes on the dorsum of 



CAUSE MYIASIS IN MAN. 235 

the thorax, characteristic of species belonging to the 
latter genus. Further distinctive characters ar« provided 
by the eyes in the male sex, and by certain bristles on 
the pleurae or sides of the thorax. In the male the facets 
forming the upper two-thirds or three-fourths of the 
eyes are conspicuously enlarged in Pycnosoma, while in 
Chrysomyia the corresponding facets are, under an 
ordinary platyscopic hand-lens, not noticeably larger 
than those below ; again, the sterno-pleural bristles are 
1 : 1 in Pycnosoina, instead of 2 : 1, as in Chrysomyia. 

I have not yet had an opportunity of studying the 
larvae of any species of this genus, but an examination of 
puparia belonging to both Indian and African species of 
Pyctiosoma shows that, instead of having thickened bands 
each bearing a number of closely set rows of minute 
spines, as in the larvae of Sarcophaga, the body-segments 
in a Pycnosoma-maggot each bear a single more or less 
complete circlet of relatively large and widely separated 
spines. 

The National Collection contains four specimens of an 
apparently new species of Pycnosonia, bred at Dehra 
Doon, U.P., India, in 1906, by Lieut.-Colonel F. Wyville 
Thomson, I. M.S., from larvae from a case of nasal Myiasis 
in an old woman. When sending the flies to the 
Museum, in January, 1907, Colonel Wyville Thomson 
wrote : " The woman discharged about 100 larvae from 
her nose, with great pain in the nasal region and frontal 
sinuses. The larvae were all got out by injections', 
and the patient recovered. 1 bred out these flies by 
putting the larvae in earth, into which they at once 
burrowed, formed, brown chrysalises and hatched out in 
about 20 days, the weather being cold." The flies 
referred to are about 7 mm. in length, and have orange- 



230 SOME DIPTEROUS INSECTS WHICH 

buff-coloured faces, chrome -yellow palpi and antennae, 
and a hoary bloom on the front of the thorax. It may 
be added that the abdominal segments are devoid of the 
dark bands on their hind margins, characteristic of most 
if not all of the described species. 

According to The Medical Times d- Gazette for January 
30th, 1875, nasal Myiasis is an ordinarily common malady 
in Rajputana, where it it known as " peenash " ; refer- 
ences to literature will be found under this name in 
Huber's " Bibliographie." 

TROPICAL AMERICA (including the 

WEST INDIES). 

With the exception of Aphiochtcea, and of bot-fly 
larvae of the genus Dermatobia (Family (Estridae), the 
Myiasis-producers in Tropical America with which I am 
at present acquainted, all belong either to the genus 
Sarcophaga or to that known as Chrysomyia, the latter 
of which, as I have already explained, is closely related 
to Pycnosoma, its representative in Africa and Tropical 
Asia. So much has already been published concerning 
the notorious Screw- worm Fly [Chrysomyia macellaria, 
Fabr.), which is found from Argentina to Texas, that it 
need not detain us now ; but a few words may be said 
as to another species of the same genus, Chrysomyia 
viridula, Eob.-Desv., which so far as I am aware has 
not hitherto been recognised as causing Myiasis in man. 

Chrysomyia viridula, Rob.-Desv. — This species, which 
is considerably larger than Chrysomyia macellaria, was 
bred by Dr. Daniels in March, 1899, in New Amsterdam, 
British Guiana, from a sore on a human being. It was also 
bred in Trinidad, B.W.I. , in 1908, by Dr. S. M. Laurence, 



CAUSE MYIASIS IN MAN. 287 

from a larva discharged with between 100 and 150 other 
maggots from the nose of a woman suffering from facial 
Myiasis {Cf. S. M. Laurence, British Medical Journal, 
Jan. 9th, 1909, p. 88, and fig.). The specimen bred by 
Dr. Daniels, which is a male, is 105 mm. in length, and 
similar to Ch. macellaria in coloration, having an ochra- 
ceous face and metallic bluish green body, with the 
dorsum of the thorax marked with the three broad, 
blackish, longitudinal stripes, characteristic of the genus 
Chrysomyia. Two puparia, which were sent by Dr. 
E. D. EowLAND with this specimen, are 11 mm. in length 
by about 4'4 mm. in greatest width, dark seal-brown in 
colour, and still show the bands of coarse spines with 
which the larval segments were encircled. The anterior 
extremity exhibits three or four longitudinal wrinkles or 
puckers on each side, and at the opposite end the posterior 
larval stigmata, instead of, as in Sarcophaga pupae, being 
situate in a pit, lie in a transverse groove. The fly bred 
by Dr. Laurence in Trinidad, and the remains of its 
puparium were figured by him in his article, where the 
insect is referred to as a " blue-bottle " ; both specimens 
are now in the British Museum (Natural History). 

Sarcophaga {species incerta). In The Journal of 
Tropical Medicine and Hygiene, Vol. XI., No. 20, Oct. 
15th, 1908, p. 305, Dr. J. H. Harrison published a 
description and illustration of a fatal case of facial Myiasis 
in a negro woman in British Honduras. According to 
the author : — " Altogether upwards of about 300 worms 
were removed," and "were found to'be larvae of Lucilia 
macellaria, commonly known as the screw- worm." An 
examination of the larvae, some 20 of which were pre- 
sented by Dr. Harrison to the British Museum (Natural 
History), shows however that they belong to Sarcophag((, 



238 SOME DIPTEROUS INSECTS WHICH 

and not to Chrysomyia. The maggots are of different 
ages and sizes, and vary in length from 11 to 18 mm. ; 
in every case the body-segments are surrounded by the 
circlets of minute spines, characteristic of larvae belonging 
to the genus Sarcophaga. 

Sarcophaga chrysostoma, Wied. — In 1899, Dr. E. D. 
Rowland, at that time Resident Surgeon of the Public 
Hospital, New Amsterdam, British Guiana (now Resident 
Surgeon of the Public Hospital, Georgetown, British 
Guiana), bred two species of Sarcophaga from larva? 
which he removed, in the course of his hospital practice, 
from a sore on a girl's foot. The larvae were extracted 
by Dr. Rowland on February 16th, 17th and 18th, 1899, 
and, in the case of one species, the flies emerged on 
March 2nd and subsequent days, while the perfect insects 
belonging to the other and much larger species began to 
make their appearance on March 8th. Dr. Rowland 
kindly presented a series of specimens and pupa-cases of 
both species to the British Museum (Natural History). 
The larger species, which I was able to identify as 
Sarcophaga chrysostoma, Wied., is one of the largest and 
most conspicuous of its genus, and eighty years ago was 
stated by its describer to occur in Brjizil and the West 
Indies (C/. Wiedemann, Aussereuropaische zweifliigelige 
Insekten, II., 1830, p. 356) ; it is, doubtless, widely 
distributed in Tropical South America, and I have met 
with it myself on the Lower Amazons. 

This large and striking-looking fly, which is about 
15 mm. (tV inch) in length, has a golden coloured face, 
three relatively broad and conspicuous black stripes on 
the back of the thorax, and ochraceous - buff anal 
segments. In the male the tibiae of the hind legs and 
the distal halves of those of the middle legs are thickly 



CAUSE MYIASIS IN MAN. 239 

furred with long hair on the inner side. The empty 
puparium or pupa-case of this species, which measures 
some 13 mm. in length by about mm. in breadth at its 
widest point, is dark reddish-brown (seal-brown) in 
colour, and, of course, of the usual barrel shape. 

The second species which, so far I have not succeeded 
in identifying, is a very much smaller fly, being only 
about 7*5 mm. to 8 mm. in length, while its puparium is 
some 7 mm. long, and of a reddish chestnut colour. 

It may be added that in Dominica, according to 
Dr. H. A. A. NicHOLLS, C.M.G., Sarcophaga plinthopyga, 
Wied., and other species of Sarcophaga which settle on 
sores are known as " Yaws-flies," since they are believed 
to be concerned in the dissemination of framboesia or 
yaws. 

When forwarding specimens in 1908, Dr. Nicholls 
wrote : — " These flies alight on sores, and in this way 
carry the contagium of yaws-disease from person to 
person. Since they will also settle on filth of all kinds 
and then on exposed articles of food, they are concerned 
in all probability with the spread of dysentery at times 
when it becomes epidemic, and they, doubtless, assist in 
the propagation of other germ diseases." 

Dermatobia. — This genus of (Estridae, which, in its 
larval stage, is normally a subcutaneous parasite of cattle 
and other mammals in Central and South America and 
the West Indies, sometimes attacks man in the same 
manner. It is seldom that an individual has more than 
one of these larvae in his body at the same time, and 
I believe that the grub is generally found in the arm or 
leg, though occasionally the face may be attacked. In 
the stage in which the maggot is usually extracted, it is 
" tadpole "-shaped, having the anterior part of the body 



240 SOME DIPTEROUS INSECTS WHICH 

swollen, and the posterior and longer portion so attenuated 
as to look like a long tail. The maggot in this stage may 
measure about 8 to 10 mm. in length, and is known in 
Cayenne as the " Ver macaque." Older larvae are thicker, 
have a strongly wrinkled and warty appearance, and are 
much less attenuated posteriorly, though the hinder end is 
still the narrower of the two. In both stages the broader 
part of the body is surrounded by a series of circlets of 
large black hooks of chitin, which, being recurved, enable 
the creature to maintain its hold in its subcutaneous cyst. 
The National Collection contains five of these larvae, all 
from different individuals. Fom* of the maggots were 
extracted in Eastern Peru, British Honduras, and 
Trinidad, B.W.I. The fifth larva, which was presented 
by Sir Francis Laking, Bart., G.C.V.O., and measures, 
after being preserved in spirit, some 9 mm. in length, 
was removed in London in 1897 by Mr, Treves (now 
Sir Frederick Treves, Bart, G.C.V.O., C.B.) from the 
side of the face of a patient who had returned from 
Central South America. Contrary to what we find in 
ordinary Muscidae, the larval stage in (Estridae, which, as 
was explained at the commencement of this paper, are 
always parasitic at this period of their existence, lasts for 
many months, and in this case it is believed that seven 
months had elapsed between the time when the egg was 
deposited and that at which the larva was removed. 

Since the perfect insect has never been bred from any 
Dermatobia larva removed from the human subject, the 
precise species which troubles man in this way is still a 
matter of some little uncertainty. In all probability, 
however, the larvae described above are those of D. 
cyaniventris, Macq., a stoutly-built fly measuring some 
11'5 to 12'5 mm. in length, with an ochraceous-bufif- 



causp: myiasis in man. '241 

coloured face, prominent upper part of the head, dark 
grey thorax, metalhc dark blue or purple abdomen, and 
brownish wings. D. yioxialis, Goudot, if really distinct 
from D; cyaniventris, Macq., is a somewhat larger species. 

Before concluding this paper, which, if it has done 
nothing else, may . at least have served as a commentary 
on Tennyson's " infinite torment of flies," I should like^to 
emphasise the fact that in many instances of Myiasis 
due to larvae belonging to the genera Sarcophaga and 
Pycfwsoma, the identity of the species causing the trouble 
is still a matter of uncertainty. Species can be deter- 
mined only from the perfect insect, and if medical 
practitioners who have to treat cases of Myiasis would be 
at the pains of breeding out the flies from some of the 
larvae removed by them, many gaps in our knowledge of 
this interesting though unpleasant subject would soon be 
filled. All that is necessary is to place the maggots on 
the top of a pot containing some fairly dry earth, and to 
cover the vessel with muslin. The flies, which will thus 
be caught on making their appearance, should be killed 
by exposure to chloroform or cyanide, but, since it is 
absolutely essential to give the integument, legs, and 
wings time to harden and to assume their natural colours, 
from 12 to 24 hours should be allowed to elapse before 
transferring the insects to the lethal chamber. For 
transmission to England they should be screwed up 
loosely in cigarette paper, and packed in a small metal 
box. The sexes can be distinguished by the eyes in 
the male being either actually in contact, or close 
together on the top of the head, while in the female the 
eyes are wider apart. Three or four examples of each 
sex are necessary, and they should be accompanied by 
their puparia, and by some of the larvae and pupae in 



242 DISCUSSION. 

spirit. All such specimens addressed to me at the British 
Museum (Natural History), Cromwell Road, London, 
S.W., and accompanied by particulars, will be gratefully 
received, and duly examined and reported upon. 



Discussion. 
Dr. C. W. Daniels said that of course in the West 
Indies they recognised the study of Diptera as an im- 
portant branch of Medicine, and one that should not 
be neglected. He had not seen any cases of Myiasis 
anywhere else except in British Guiana that attacked 
extensively the nasal or other passages. In British 
Guiana the larvae of Dermatobia were found in the 
uncovered parts of the body, whilst in the African 
Tumbu-fly it was usually round the waist, or in covered 
parts of the body. It looked therefore as if the larvae 
were deposited in rather a different way. One could 
actually breed from ulcers — whether dirty, sloughy and 
neglected ulcers or comparatively clean ulcers. From 
the former one could breed a great variety of flies, whilst 
from the latter few species of fly seemed to be produced. 

Dr. F. M. Sandwiih said he would hke to say a few 
words which might appeal to Mr. Austen not so much 
from the entomological as from the military point of 
view. Mr. Austen mentioned in the first part of his 
paper the experience of surgeons in the Crimea who 
found maggots in the wounds of soldiers. In August, 
1877, in the Russo-Turkish war, he (Dr. Sandwith) was 
at the Shipka Pass, where a large number of Turks were 
wounded. The official report gave the number of 
wounded passing through the ambulance tents within 
eight days as 10,000, and there were only two surgeons 



DISCUSSION. 243 

capable of operating. A large number of the soldiers 
were shot through the head and died on the field, but 
many others wounded in the head or face while fighting 
behind entrenchments, came to them within two or three 
days with their wounds literally filled with maggots. 
The extraction of these maggots from the sinuses of the 
head and face was a most disgusting process, and they 
found the only effective method was to wash them out 
with carbolic (1 in 40) or with a strong solution of salt. 
To remove the maggots entirely, the wounds required to 
be well syringed morning and evening for two days. On 
one occasion during the campaign he discovered 200 men 
whose wounds had only once been dressed in the nine 
5ay8 since the battle ; maggots and stench were banished 
in two days by the vigorous use of carbolic acid and 
Condy's fluid. 

Dr. Oswald Baker thanked Mr. Austen for his 
interesting and instructive paper, and regretted that he 
had not sufi&cient entomological knowledge to discuss it. 
He could only say with reference to the case of Myiasis 
reported by him, to which Mr. Austen had alluded, that 
there was no doubt in his own mind that certain dipterous 
flies were capable of living and propagating their species 
within the human intestine. He ventured to think that 
no one who had before him the evidence that had been 
presented to him could come to any other conclusion. 
The alvine evacuations of his patient contained maggots 
of different generations, some almost microscopic, others 
mature, about ^ of an inch long ; while the patient him- 
self asserted that he had passed living flies on several 
occasions ; and these phenomena persisted for months, 
notwithstanding the use of a diet, consisting exclusively 
of milk and farinaceous substances. 



ox THE NATURE AND ORIGIN OF CALABAR 
S^VELLINGS. 

[By Sir PATRICK :!J:ANS0N, K.C.M.G., F.R.S.] 



Medical men who have much to do with patients 
from West Africa, more particularly with patients from 
Southern Nigeria, The Cameroons, French Congo and the 
Congo Free State, must frequently have seen cases of the 
West African disease known as Calabar Swellings, and 
been puzzled about the nature and etiology of this 
peculiar condition. 

In an individual, probably otherwise healthy, an 
oedematous non-inflammatory swelling many inches in 
diameter suddenly and without obvious cause appears 
on a limb, or on trunk, head or neck. In a few 
hours the swelhng, without redness or pain or other 
sign of inflammation or at most with a bruised or tense 
feeling, attains its maximum development and then, 
during the next day or two and without further trouble, 
slowly subsides. It never suppurates. This is what is 
known as a Calabar Swelling, so called because such 
swellings are common in and near Calabar. In the same 
subject they recur at irregular intervals of weeks or months 
during many successive years, and even long after the 
patient has left Africa for good. At one time the swelling 
is in one place, at another time in another place ; 
occasionally, in certain individuals, it appears to have 
a predilection for a particular locality, notably the hands 
and forearms ; but any area on the surface of the body 
may be attacked. I have never seen nor heard of a 
mucous surface being involved, but I am not in a 
position to assert that such surfaces are exempt. This is 



CALABAR SWELLINGS. 245 

an important point, and one requiring further investiga- 
tion ; for although a fugitive cedema involving the 
surface of the body may be of little importance as affecting 
life, a similar oedema occurring about the fauces, the 
larynx or urethra would be a very serious matter indeed, 
and may be the explanation of some of those sudden 
deaths we hear of from time to time as occurring in 
West Africa. Although I have seen a good deal of 
mental distress resulting from their presence and 
frequent recurrence, ordinarily a Calabar Swelling is 
more curious than important, 

The object of the present communication is to suggest 
an explanation of this curious and it may be important 
disease, and to request those who have the opportunity 
to repeat an observation recently made, which, so far as 
it goes, tends to support a hypothesis formulated and 
published some years ago. 

Though there are still many points to be cleared up on 
the subject, I take it that nowadays it is generally believed 
that these Calabar Swellings are in some way brought 
about by Filaria loa or by its larval microfilaria. The 
frequency with which this parasite and these swellings 
are associated in the same individual, and the identity so 
far as known of their respective geographical ranges and 
topical distributions distinctly point to this conclusion. 
It is quite true that in many cases of Calabar Swellings 
neither Filaria loa nor microfilaria loa have been or can 
be demonstrated : but it is equally true, as has been 
pointed out by others as well as by myself, that in many 
instances microfilaria loa is present in profusion in the 
blood and yet no Filaria loa has been seen crossing the 
eye or recognized under the skin ; and, conversely, that 
gravid Filaria loa are sometimes seen in the eye and yet 



246 CAIiABAB SWELLINGS. 

no microfilaria are to be found in the blood. Evidently 
the parasite may be and often is lying and moving about 
in the tissues without betraying its presence either by 
showing itself in the eye, or beneath the skin, or by the 
presence of its young in the general circulation. Simi- 
larly, in those cases of Calabar Swelling in which neither 
the loa nor its microfilariae have been detected, the 
parasite must nevertheless be present in some part of the 
body. It is easy to understand how larvae may be found 
in the blood and yet the parent worms remain concealed 
in the deeper tissues ; but why the larvae do not show 
themselves in the blood in every instance of loa infection 
is not so easily understood, nor can I explain it. I know 
however for a fact that gravid loas may show themselves 
from time to time, and yet careful and repeated blood 
examinations, made at presumably appropriate times, 
may be fruitless as regards detection of haematozoal 
larvae. The absence of larvae from the blood therefore 
is not a valid argument, as some have maintained, against 
the filarial origin of Calabar Swellings. 

Filaria loa is a connective tissue nematode an inch 
and half to two inches or more in length, and about the 
thickness of a medium -sized sewing needle. The uterus 
of the mature female is packed. with sharp-tailed and 
sheathed larvae in every respect identical with the 
haematozoal larvae of diurnal habit, formerly called 
Filaria diurna but now more appropriately designated 
microfilaria loa. The parent worms, as conclusively 
shown by Brumpt, Wurtz and Penel, may be present 
in large numbers. They wander about the body in the 
connective tissue, sometimes traversing the subcon- 
junctiva and showing themselves there, sometimes 
travelling just under the skin of the trunk or limbs or 



CALABAK SWELLINGS. 247 

face, where, on approaching the surface, they cause a 
little itching, and where their presence may sometimes 
be recognised by a slight serpentine elevation distinctly 
visible as the underlying worm travels along in vermi- 
cular fashion at about the rate of half an inch a minute. 
Ordinarily, even when close under the skin, the parasites 
cause no marked swelling unless the part be scratched 
or irritated. How their larvae contrive to enter the 
general circulation is not known ; probably on being 
emitted into the connective tissue they find their way 
along the lymph spaces into the lymphatics and so into 
the blood. 

That the adult worm does not usually give rise to 
much irritation or to pronounced swellings I am con- 
vinced, for months may elapse, the worms all the while 
moving about the body, and yet no Calabar Swelling 
appear. Some years ago I had a patient whose blood 
teemed with microfilaria loa, and who used to amuse 
himself by harpooning with a needle the adult loas as 
they wriggled their way under the skin on his chest or 
abdomen. He became quite an expert at this form of 
sport, and on three occasions sent me what I might term 
the fruits of his spear in the shape of fragments of 
mutilated loas which he had succeeded in impaling. 
Evidently this man was the host of a large number of 
these parasites, and yet, though the worms were 
numerous and active, it was only at long intervals that 
he had a Calabar Swelling. The mere presence and 
movements of the worms therefore do not cause the 
characteristic oedema. 

Thinking about this matter it occurred to me that 
Calabar Swellings must be produced in one or other of 
four ways. 



248 CALABAE SWELLINGS. 

(a) By lymphatic obstruction. This I dismissed as 
untenable, seeing that the worm lies not in a lymphatic 
vessel, but, so to speak, free in the connective tissue. 

{b) By some irritating glandular secretion emitted 
from time to time. This too I dismissed as I failed to 
understand the object, viewed from the standpoint of 
the interests of the parasite, of such a secretion. 

(c) By faecal discharges from the alimentary canal of 
the worm. This too I dismissed as unlikely, seeing that 
such discharges were probably of frequent occurrence, 
whereas Calabar Swellings are relatively infrequent; nor 
could I see any object in the interests of the parasite why 
nature should have endowed the faeces of the animal 
with irritating properties. 

{d) Lastly, by periodical and normal emptying of the 
contents of the uterus of the gravid female worm into 
the connective tissue of the host. 

This last was the hypothesis I favoured, because it 
appeared to me to conform with the interests of the 
parasite as well as to explain the phenomena of the 
disease. One can understand how a mildly irritating 
action, such as could be produced by the moving larvae, 
would, by causing the effusion of a large quantity of 
serous fluid, assist the emitted larvae to move along the 
now distended lymph spaces and be flushed into the 
lymphatic vessels and so finally into the general circula- 
tion. It is well known that if a Guinea worm, also a 
connective tissue parasite, be ruptured by indiscrete 
traction and her larvae in vast numbers thus discharged 
into the connective tissue she lies in, almost immediately 
an oedematous swelling, comparable in a sense to a 
Calabar Swelling, results, provoked doubtless by the 
irritating properties of the larvae or other contents of the 



CALABAR SWELLINGS. 249 

uterus of the ruptured worm. The analogy seems to 
favour my speculation. 

For several years I have been on the outlook for an 
opportunity to test this hypothesis as to the nature and 
origin of Calabar Swellings. Some three or four years 
ago I attempted to prove it by examining the serous 
contents of one of these swellings, but as in that instance 
the swelling was of some standing and subsiding at the 
time, it did not afford me the best chance of success, and 
I failed to obtain the evidence I was in search of. 

I have many times asked such patients to come to me 
for examination immediately on the first indications of 
the commencement of one of their Calabar Swellings, 
but it was only recently that I succeeded in getting 
a suitable opportunity. The patient in question had 
resided for several years in Southern Nigeria. His blood 
teemed with microfilaria loa and, in addition, it con- 
tained a few microfilaria perstans. For several years he 
had been troubled with Calabar Swellings. I told him 
to come to me at once should he be in London when one 
of the swellings commenced. One evening, about 8.30, 
early in January of this year he turned up at my house 
with a well-marked Calabar Swelling on the back of his 
left hand. He informed me that it began about one or 
two o'clock the same afternoon. The back of the hand 
was much swollen. His friends had told him it was the 
gout. He knew better ; there was no pain. I got him 
to indicate precisely what he considered to be the 
starting point of the swelling, and he»referred me to a 
spot between the metacarpal bones of the ring and 
middle fingers of the left hand, about an inch from the 
knuckles. On my pressing here with the tip of my 
finger he said it was slightly tender. I marked the spot 



250 CALABAR SWELLINGS. 

with a dot of ink, and entering a hypodermic needle 
about three quarters of an inch from the indicated spot, 
I pushed the needle through the cedematous tissues till 
the point lay under my mark or perhaps a little beyond. 
I then aspirated, endeavouring to withdraw some of the 
effused serum into the sjrringe. Nothing showing in Ijhe 
barrel of the syringe I detached this from the needle and 
then withdrawing the needle blew the contents of the 
latter on to a microscope slip. I obtained in this way a 
droplet of clear fluid which appeared to the naked eye 
quite untinged with blood. I repeated the operation 
and made a second preparation, in both instances spread- 
ing the small quantity of fluid over about half an inch 
square of the slip. After allowing the films to dry, I 
stained one with carbol-fuchsin, the other with logwood. 
There was very little blood ; here and there only one or 
two red blood corpuscles. On the other hand there were 
many polymorphonuclear leucocytes, and in one slip 
thirteen and in the other slip seven microfilariae possess- 
ing all the characters of microfilaria loa. 

It must be conceded, I think, that these findings are 
strong evidence in favour of my hypothesis. I do not 
claim that they prove it. There are possible fallacies 
which cannot be ignored. For example, the patient's 
blood contained many microfilariae at the time the 
swelling was explored, and it may be that some of these 
had escaped with the serum that was rapidly being 
effused into the connective tissue ; or it may be that my 
needle tapped some capillary in which an unusual number 
of microfilariae had accumulated. All I claim for the 
observation is that it supports my hypothesis, and, more- 
over, that it justifies a repetition of a similar investigation 
in suitable cases. Personally I may not have another 



CALABAR SWELLINGS. 251 

opportunity ; but others are sure to have, and I trust 
they will take advantage of it and report the result. 

There are one or two points which must be carefully 
attended to in carrying out such an investigation. In 
the first place the swelling must be quite recent, only of 
a few hours' standing, and on the increase ; and, second, 
the exploration must be made as near as possible to the 
point of origin of the cedema ; and, lastly, when aspira- 
tion is made the needle-point must lie in the cedematous 
tissue. Any preparation containing much blood should 
be rejected. I would prefer to explore Calabar Swellings 
in the case of patients in whose blood there are no micro- 
filariae to be found, for, if in such a case microfilariae 
were obtained from the oedematous swelling, they could 
not be regarded as coming from accidentally aspirated 
blood, and my hypothesis will be proved to be correct. 
Any medical man, and I suppose there are such, who is 
himself the subject of Calabar Swellings, or who is in 
daily association with Calabar Swellings patients, could 
easily settle this interesting and perhaps important point 
in tropical pathology. 



Discussion. 
Dr. G. C. Low said he would like to make one or two 
remarks on Sir Patrick Manson's very interesting paper. 
Personally he (Dr. Low) agreed with Sir Patrick's idea 
that the Calabar Swellings were due to the Filaria loa, 
and he thought that the hypotheses put forward to explain 
their origin were distinctly ingenious, and in all prob- 
ability correct. Of course, as regards the experiment of 
drawing lluid from the swelling, the results — as Sir 
Patrick himself admitted — were vitiated by the possible 
contamination of blood, the patient having numerous 



252 DISCUSSION. 

filarial embryos in his peripheral blood at the time of 
puncture. To make such an experiment perfect, one 
would require to take a person with no embryos in the 
peripheral blood, and then puncture a Calabar Swelling, 
and demonstrate the embryos in the juice removed. He 
thought that any of the medical men practising in 
Calabar and that neighbourhood, could try such an ex- 
periment, practically at any time, and so settle the point. 
As regards the relationship of the diurnal embryos (F. 
diurna) found in the blood of people coming from 
Southern Nigeria and the neighbouring colonies, with 
the young or embryonic forms of the Filaria loa, and 
their difference from the young of Filaria bancrofti, he 
again entirely agreed with Sir Patrick, and could adduce 
further points in favour of the correctness of these views. 
In text books and other places, it was generally stated 
that the young embryos expressed from the uterus of the 
adult female Filaria loa were identical with the diurnal 
forms found in the peripheral blood in the same districts, 
but that the latter were, to all intents and purposes, 
identical with the microfilaria bancrofti. The latter part 
of that statement he (Dr. Low) wished to show was 
incorrect, as from a series of careful measurements he 
made some years ago, he came to the conclusion that the 
microfilaria loa (F. diurna) found in the peripheral blood 
presented different measurements to the embryos of 
Filaria bancrofti. The former measured from "210 to "280 
of a millimetre in length (average measurement '240 ram.), 
the latter (m.f. bancrofti) from "290 to 320 of a milli- 
metre in length (average measurement '310 to "317 mm.), 
the v spot in the former being situated 060 mm. from 
the head, in the latter 090. mm. from the head. That 
clearly shewed that the two embryos were distinctly 



DISCUSSION. 253 

different, and could not be the same. Further, the 
average measurement of 30 embryos expressed from the 
uterus of an adult Filaria loa, sent to him by Dr. Currie, 
of Lagos, gave a length of '245 mm., an exactly similar 
figure to the so-called F. diurna. He believed, therefore, 
that the time had come for abolishing the name Filaria 
diurna and substituting in its place the term microfilaria 
loa. At the same time, however, he would sound a word 
of warning as to any filaria embryo seen in the blood by 
day being called a microfilaria loa. The embryos found 
in the Philippines and Fiji — embryos which appeared to 
occur as frequently in the blood by day as well as by 
night — might only be microfilaria bancrofti with an 
irregular periodicity, or they might even represent another 
species, but certainly they were not the microfilaria loa. 
He thought that the complete diurnal periodicity was a 
very strong point in the case of the diagnosis of micro- 
filaria loa, the inability to change the periodicity of this 
filaria by inverting the habits of the patient — an experi- 
ment he had very carefully carried out on one of Sir 
Patrick Hanson's cases at the Seamen's Hospital — 
being another point which clearly separated the embryos 
from those of F. bancrofti, and was one — if its constancy 
was confirmed in other cases — which he (Dr. Low) 
thought might be made use of in the future. 

^ Dr. T. B. Adam said he had seen one or two cases in 

which there were no swellings at all. One case sufi"ered 
from Filaria for a period of 25 years, and he bad had 
between 20 or 80 filariae removed. When one was 
removed within a few days another would come, and* then 
it might be a considerable time before he got more. The 
day after he stated that he never had a swelling, a small 



254 DISCUSSION. 

swelling appeared on the back of his right hand, quite 
typical of Calabar swelling. As to the question of their 
being oedematous he thought it was only occasionally 
that they were so. Also as to the symptoms lasting only 
two or three days he thought it was not uncommon for 
them to last two or three weeks, and sometimes longer. 
He had made an attempt in one case to communicate 
Filaria from one subject to another by means of mos- 
quitoes. He did not know enough about entomology to 
name the species, but the mosquitoes used belonged to 
the culioini, he had got them to feed on a patient who 
had had Filaria loa of the eye. About two years after the 
infection of the eye Filaria loa were found in the patient's 
blood, and at the time of the experiment were in his 
blood. About three weeks after they fed on the infected 
patient he got them to feed on a man who had no micro- 
Filaria loa in his blood, whom there had been no 
swellings and no Filaria in the eye. About a month 
later this man had his first swelling, and the loa has since 
appeared in the eye. It was unfortunate that he lived 
where a considerable number of natives were infected, as 
this vitiated the experiment. He hoped personally to 
afford an opportunity in the near future of repeating 
Sir Patrick Hanson's experiment, which would be 
more conclusive, as he had no micro filariae. 

Dr. R. Leiper said he thought that the only crucial 
experiment that could set aside the theory would be the 
discovery of male sex in a worm that caused a Calabar 
swelling and not whether there were embryos in the 
blood. He did not regard this latter point one of im- 
portance ; moreover, the experient took place at night. 
Sir Patrick Manson did not discuss the catme of the 



DISCUSSION. 255 

sudden " swelling " of the embryos out of the worm 
under certain conditions, and the absence of these when 
the mature worm was present under the skin in other 
conditions. Were they normal ? Might they not have 
something to do with the nipping or catching of the 
worm during its progress ? He would like to know- 
Sir Patrick Manson's view as to the position of the 
adult Filaria in these Calabar swellings. When one 
recollected the anatomy of the worm, the presence of 
numerous minute bosses on the skin, its tapering from 
the thickened end gradually towards the posterior, one 
could easily understand that if it got into a difficiilt 
position or became caught between strands of fibrous 
tissue, it might then be unable to release itself easily, 
owing to its shape and its muscular efiforts might induce 
an unpremeditated labour. This might be the cause of 
the swelling. 

Professor Ronald Ross said he would like to ask 
Sir Patrick Manson to let them have some estimate as 
to the number of embryos in the patient's blood ; and 
also if he could tell them the number of embryos found 
in the small drop of serum taken from the swelling. 
That might help them in coming to some conclusion as 
to whether the embryos found in the serum had or had 
not come from an accidental admixture of blood. 

Sir Patrick Manson in reply said that the patient 
hsbd an enormous number of larval filariae in his blood at 
the time of observation. He thought there were about 
50 on the slide, which was about f-inch, and fairly thick. 
It was a heavily infected case. One speaker had 
mentioned the occurrence of Filariee in pairs. It was a 



256 DISCUSSION. 

remarkable thing ; he had noticed before that these 
parasites did appear to travel through the tissues in pairs. 
Perhaps one loa would pass over the eye and it was by no 
means unusual that another loa followed, the suggestion 
being that the male hunted the female through the tissues 
or vice versa. The patient he referred to" as an expert 
at impaling the loa, and who had sent him (Sir P. 
Manson) two or three mutilated loa procured in this way, 
observed that they usually appeared one after another, as 
if following each other. As to the cause of the swelling 
suggested by Dr. Leiper, that he was not qualified to 
discuss ; it was quite possible, but whether it was so he 
could not tell. The loa had a predilection for particular 
parts of the body, especially the backs of the hands and 
forearms ; it was strange that they should get nipped, 
especially there, and not in other situations. The whole 
subject of Filaria loa required much more study ; it 
prevented many problems as yet unsolved. 

The President thanked Sir Patrick Manson for his 
Paper and congratulated him on obtaining this evidence 
of a theory which he knew Sir Patrick had held for 
fifteen years. 



THE ETIOLOGY OF BEKI-BEKI, 

BY 

H. FRASER, M.D. (Aber.), 
Director, Institute for Medical Research, Federated Malay States. 

AND 

A. T. STANTON, M.D. (Tor.), 

Bacteriologist, Institute for Medical Research, Federated Malay States. 



The suggestion of a causal relationship between the 
consumption of white rice and the disease Beri-Beri was 
first formally made in this country by Braddon^ This 
observer also drew attention to the important fact that 
those who consumed rice that had been parboiled before 
husking remained free from the disease, as did also the 
native Malays who consumed rice prepared by primitive 
methods of pounding and winnowing. 

A series of observations made by the writers^ in 1907 
on two parties of labourers under conditions which ex- 
cluded or adequately controlled the operation of factors 
other than diet, confirmed the correctness of this view of 
the causation of the disease. The prior observations of 
Fletcher^ and Lucy^ in this country, and of Dubruel^ 
in Indo-China, and the recently published observations of 
Ellis,^ furnish further testimony, and it may now be 
claimed that the theory rests on a solid basis of evidence. 

The mechanism by which white rice was able to 
produce this result has remained in obscurity. Braddon 
suggested that " the cause of this disorder is not indeed 
rice, qua rice, or as an article of diet, but diseased rice; 
rice from which poison derived from decay, due perhaps 



258 THE ETIOLOGY OF BERI-BERI. 

to some fungus, or mould, or germ, or spore, originally 
perhaps growing upon the husk has become mixed 
during the process of milling ; or upon which such 
fungus may have grown and such poison have been 
produced after decortication." Eijkman,' from experi- 
ments on fowls, concluded that a definite poison exists 
commonly in rice, and that for this poison or its effects 
something or substances in the pericarp was an antidote. 
DuBRUEL conceived the ingestion of an organism asso- 
ciated with white rice, which organism multiplying in the 
body produced the disease. 

Following the line of thought suggested by the poison 
hypothesis researches were undertaken to determine 
whether from white rices actually associated with out- 
breaks of beri-beri there could be extracted by means 
of various solvents any substance or substances recog- 
nisable by chemical or biological methods as poisonous 
in character. These researches failed of their object, 
though it is admitted that the accuracy of the poison 
hypothesis was not thereby disproved. 

Certain results which emerged from chemical analysis 
and histological examination of the rices turned atten- 
tion to the possibility of an explanation of the course 
of events on an hypothesis of a defect of nutrition. 
That this explanation was inadequate, if dietary con- 
stituents as estimated by the ordinary analytical methods 
were alone considered, had been shown in the pre- 
liminary investigation. 

By a series of experiments on domestic fowls the 
details of which will be supplied in a later publication, 
it was shown that these animals when fed on various 
kinds of rice were sensitive to differences between 
them. By further and repeated experiments with 



THE ETIOLOGY OF BERI-BERI. 259 

rices known to have been associated with outbreaks of 
beri-beri> and with controls under identical conditions 
fed on parboiled rice, it was established that a certain 
reaction in fowls might be taken as an indicator of 
the beri-beri producing power of a given rice when form- 
ing the staple of the diet in man. Whether the disease 
produced in fowls be accepted or not as analagous to 
beri-beri in man, the validity of the arguments here 
advanced remains unimpaired. Rices were available 
that were known to have been associated with outbreaks 
of beri-beri ; samples had been taken daily during the 
continuance of the preliminary inquiry in 1907, and 
through the courtesy of Dr. J. D. Gimlette and Dr. G. D. 
Freer we were enabled to procure white rice which was 
being consumed prior to an outbreak of beri-beri among 
Malays at the Kuala Lumpur Police Depot, which out- 
break ceased on changing the rice supplied to the par- 
boiled variety. It was shown that these rices when 
fed to fowls constantly produced a certain disease in a 
large portion of them, while parboiled rice as constantly 
failed to produce this result in groups under identical 
conditions. It is our behef that this disease, Poly- 
neuritis gallinanmi is truly analagous to beri-beri in 
man, similar in its etiology, in its clinical manifesta- 
tions and in its pathological effects, and that its occur- 
rence should be held as important confirmatory 
testimoay of the connexion between white rice and 
beri-beri. It is desirable, however, to emphasise the 
point that the acceptance, or non-acceptance of this 
opinion is immaterial to the argument ; for this pm-pose 
the occurence of the disease is employed only as a 
reaction. The fact that certain white rices when form- 
ing the staple of a diet in man produce beri-beri rests 



260 THE ETIOLOGY OF BERI-BERI. 

on quite other testimony than that supphed by experi- 
ments on domestic fowls. 

The commercial varieties of white rice are nmnerous, 
but in this country, apart from the grading as to quality, 
two varieties are in common use, and are known 
respectively as Siam and Eangoon. 

From epidemiological considerations and from experi- 
mental evidence it appears that Siam rice is considerably 
more potent in its beri-beri producing powers than 
Eangoon rice. 

The proteins, fats, carbohydrates, and ash were deter- 
mined for the different varieties of rice which had been 
employed in the experiments, with the following per- 
centage results calculated on dried material : — 

Protein. Fat. Carbohydrate. Ash. 
White rice (Siam) ...9-07 017 9011 065 
White rice (Eangoon) 8-44 081 89-90 0-85 
Parboiled rice ... 9'48 051 8912 089 

A comparison of these results shows that the only 
markea difference among the rices was in respect of 
fat, which was most abundant in the variety known as 
Eangoon, less abundant in parboiled rice, and still less 
abundant in Siam rice. These observations, taken in 
conjunction with the experimental results in fowls, 
excluded the possibility of an explanation of the origin 
of beri-beri on the ground of a deficiency in fat. It 
will be noted that these analyses did not include an 
estimation of the relative proportions of the inorganic 
salts composing the ash, nor did they take account of 
the manner of combination, organic or inorganic, in 
which these substances originally existed in the rice grain. 

By a method devised in this laboratory, sections of 
the various rice grains were obtained of sufficient 



THE ETIOLOGY OF BERI-BERI. 261 

thinness to permit the examination in detail of their 
histological characters. By suitable staining methods 
it was shown that in parboiled rice remnants of the 
pericarp remained attached to the rice grain, whereas 
in Siam rice the pericarp and the layers subjacent to 
it had been polished away. It would appear that par- 
boiling renders the grain tough and non-friable, in 
consequence the peripheral layers cannot be removed so 
readily as in the untreated grain. It was further 
demonstrated that the layers so retained in parboiled 
riice contained the most of the aleurone and oily 
material present in rice grains. The reason for the 
difference between these rices in respect at least of fat 
was thus clearly demonstrated. Kice as prepared by 
primitive methods (Malay rice) was similarly examined, 
and, as might have been expected from the pounding 
to which this rice had been subjected, parts of the peri- 
carp and subjacent layers were chipped off to a varying 
extent, but on the whole these layers were retained to 
a greater extent than is the case with white rice. 

Early in the course of the experiments the observation 
was made that parboiled rice, subjected to exhaustion 
with hot alcohol and thereafter carefully dried in the sun 
to free it from alcohol, produced when fed to fowls a 
disease indistinguishable from that observed in fowls 
fed on white rice, though such parboiled rice in its original 
state was incapable of producing this result however long 
continued. 

The association of the observations referred to in the 
two preceding paragraphs seemed to point a way to a 
solution of the problem. It had been shown that white 
rice as prepared in the mills of this country produced 
the same results in fowls as white rice known to have 



262 THE ETIOLOGY OF BERI-BERI. 

been associated with beri-beri. If now a substance or 
substances residing in the outer layers which are milled 
away in white rice and are retained in parboiled rice 
could be added to white rice, and so prevent its harm- 
ful effects, it was conceived that the nutritive hypothesiB 
Woulil thereby be supported. 

In accordance with this idea the following experiments 
were initiated : A rice mill in Singapore was visited, and 
there was obtained (a) a quantity of the original padi 
then being milled — in this case a partially husked padi 
imported from Indo-China ; (6) a quantity of the finished 
product as it came from the machine ; (c) a quantity of 
" polishings " from the same rice, Polishings, it may be 
stated, consist of the outer layers of the seed removed in 
the process of making the rice white. The miller 
estimates that 40 parts of padi produce 25 parts of white 
rice, 5 parts of polishings and 10 parts of husk. The 
polishings are sold as food for cattle, and the husks are 
burned as fuel in the mill. 

Experiment A . — Twelve fowls were fed on the padi for 
five weeks. 

Besult. — All remained healthy. 

Experiment B. — Twelve fowls were fed on the white 
rice alone. 

Result. — In five weeks six had developed polyneuritis ; 
two were dead, one having suffered from polyneuritis and 
one from a disease other than polyneuritis ; five fowls 
remained healthy. 

Experiment C. — Twelve fowls were fed on rice taken 
daily from the same bag as that used in Experiment B. 
In addition polishings in the form of emulsion, in amount 
equal to that milled from the quantity of rice consumed, 



THE ETIOLOGY OF BERI-BERI. 268 

was fed by a tube passed into the crop daily. This 
quantity was subsequently diminished week by week, 
until only three grammes per kilogramme of body weight 
was being given daily, which amount sufficed to maintain 
the fowls in health and in constant weight. 

Kesult. — The experiment was continued for seven 
weeks, and all remained healthy. 

This result was subsequently confirmed for rice from 
known outbreaks of beri-beri. 

It will be understood that these three experiments were 
in progress simultaneously, and that the fowls were in all 
respects under identical conditions. 

Experiment D. — Part of the original padi was taken 
and milled by a Malay woman by primitive methods into 
the finished product as eaten by Malays. Eight fowls 
fed for five weeks on the rice prepared from the original 
padi by the Malay method, all remained healthy. Eight 
fowls only were used for this experiment, as the quantity 
of padi then remaining sufficed only for this number for 
the time it was estimated the experiment would last. 

Attention is drawn to the important point that the 
products used in these experiments were all derived from 
the same lot of padi, and the results force us to the 
conclusion that it is the milling process which is essentially 
at fault ; the polishing of white rice removes from the 
seed some substance or substances essential to the main- 
tenance of the normal nutrition of nerve tissues. 

To elucidate the point as to whether rice when freshly 
milled is less harmful than that which has become stale, 
an assistant was stationed in Singapore, who sent daily 
to the laboratory by the most expeditious route a quantity 
of rice milled on the day of despatch. Twelve fowls were 
fed on this rice and five developed polyneuritis in four 



264 THE ETIOLOGY OF BERI-BERI. 

weeks. This result, which is similar to that obtained in 
other experiments when fowls were fed on rices milled 
from four weeks to two years, previously disposes of the 
suggestion that the harmfulness of white rice is due to its 
staleness or to the development in it of a poisonous 
substance or substances subsequently to its being milled. 
The root of the evil lies in the milhng process itself. 
The result further indicates the inadequacy of preventive 
measures founded on the poison hypothesis in regard to 
the use of freshly milled rice. 

An experiment was now planned to determine whether 
a parboiled rice, proved harmless, could by exhaustion 
with hot alcohol be reduced to such a condition that it 
would produce polyneuritis when fed to fowls, and whether 
the substance so extracted when fed to fowls with a white 
rice proved harmful, could prevent the development of 
polyneuritis. For this purpose parboiled rice was re- 
peatedly exhausted with hot alcohol. The alcoholic 
extracts were concentrated in vacuo at a temperature of 
52° C, freed from alcohol, and the residue emulsified in 
distilled water. Experiments with these products showed 
that fowls fed on the exhausted parboiled rice contracted 
polyneuritis, and that fowls fed on a white rice proved 
harmful by previous experiment remained healthy if they 
received in addition a quantity of emulsion. 

Having by these and other experiments, the details of 
which are omitted, so as not to encumber the argument, 
arrived at the point when it was clear that the essential 
cause of beri-beri was to be sought for in a nutritive 
defect^ further efforts were made to determine by chemical 
methods precise differences between various rices. Such 
differences, if they are to furnish an adequate explanation 
for the origin of beri-beri must be in accordance with 



THE ETIOLO(n' OF BERI-BERI. -id') 

clinical observations and the experimental results in 
fowls. 

Acting on a suggestion made to one of us by Dr. 
F. W. MoTT, F.R.S., an attempt was made to estimate 
the lipoids of the different rices, but as the time 
element enters so largely into these estimations, and 
our experiments with fowls were proceeding rapidly, it 
was decided to determine the amount of phosphorus 
calculated as phosphorus pentoxide in the various rices 
in use. It speedily became apparent from these analyses 
that the phosphorus content of the different rices varied 
with their known harmful influence, the less phosphorus 
contained in a given rice the more liable was it to 
produce polyneuritis gallinarum in fowls, conversely the 
higher the phosphorus content the less likely was it to 
produce polyneuritis. 

Thus a sample of parboiled rice, which was fed to 
fowls over many weeks, all remaining healthy, was found 
to contain '469 per cent. P.2O5, and a sample of white 
rice which produced polyneuritis in fowls yielded 
"277 per cent. P^O^. The rice polishings employed in 
Experiment C. yielded 42 per cent. P2O5. 

From a series of observations it was determined that a 
fowl under the conditions of our experiments weighing 
from say 1,200 to 1,400 grammes required 60 grammes 
of parboiled rice daily to maintain its health and nutri- 
tive equilibrium. In Experiment C. it was determined 
experimentally, the chemical analysis being then 
unknown, that when fed on white rice a fowl of this 
weight required the addition of about 3" 5 grammes of 
polishings to preserve it in nutritive equilibriimi. From 
the data given above it may be readily calculated what 
amount of polishings added to white rice is required to 



266 THE ETIOLOGY OF BERI-BERI. 

raise the phosphorus content of the white rice diet to that 
of the parboiled rice diet. Thus — 

60 grammes of parboiled rice "3120 grammes P2O.,. 

60 „ white ,, "1662 



Difference ... 1458 „ P.^O^. 

Polishings contain 42 per cent, phosphorus pentoxide. 

« 
Calculated from the phosphorus content therefore 

3'474 grammes of polishings added to the 60 grammes of 

white rice supplied to a fowl of 1,200 to 1,400 grammes 

weight will preserve it in nutritive equilibrium. From 

experimental observation 3"5 grammes of polishings had 

been shown to accomplish this result. 

There is thus afforded curious striking testimony to 
the value of phosphorus estimation as an indicator of the 
likelihood of a given rice to produce polyneuritis when 
fed to fowls, or following the argument the likelihood of 
its producing beri-beri when forming the staple in the 
diet of man. 

We are greatly indebted to Mr. B. J. Eaton, chemist 
in this Institute, for valuable assistance in the chemical 
part of this investigation. 

Dr. H. ScHAUMANN has had the goodness to send us 

recently a copy of his address before the German Society 

of Tropical Medicine in which he stated his conjecture 

(Vermutimg) that beri-beri was a disease of metabolism 

associated with a diet deficient in organically combined 

phosphorus. 

SUMMARY. 

1. Beri-beri is a disorder of nutrition, and as it 
occurs in this country is associated with a diet in which 
white rice is the principal constituent. 

2. White rice, as produced in the mills here, com- 
monly makes default in respect of some substance or 



THE ETIOLOGY OF BERI-BEBI. 207 

substances essential for the maintenance of the normal 
nutrition of nervous tissues. These substances exist in 
adequate amount in the original grain, and in superabun- 
dant amount in the polishings from white rice. 

8. The estimation in terms of phosphorus pentoxide 
of the total phosphorus present in a given rice may be 
used as an indicator of the beri-beri producing power of 
such rice when forming the staple of a diet in man. 

4. The prevention of beri-beri in this country will be 
achieved by substituting for the ordinary white rice a rice 
in which the polishing process has been omitted or carried 
out to a minimal extent, or by the addition to a white 
rice diet of articles rich in those substances in which 
such white rice now makes default. One such article, 
which is cheap and may readily be obtained, is the 
polishings from white rice. 

The use of parboiled rice, as suggested by Dr. Braddon, 
will achieve a like result, provided that the polishing 
process is not carried beyond the limited extent now 
customary. 

REFERENCES. 

1. Braddon, W. L. " The Etiology of Beri-beri." Federated Malay 

States Medical Archives, 1901. " The Cause and Preven- 
tion of Beri-beri." 1907. 

2. Eraser, H. & Stanton, A. T. " An Inquiry concerning the 

Etiology of Beri-beri." Lancet, 1909, " An Inquiry 
concerning the Etiology of Beri-Beri." Studies from 
the Institute for Medical Research, 1909. 

3. Fletcher, W. " Rice and Beri-beri.' Lancet , 1907 . " Rice and 

Beri-beri." Journ. of Trop. Med. and Hygiene. 1909. 

4. Lucy, 8. H. R. Address British Medical Association, Penang. 

1905. 

5. DuBRUEL. " Le Beri-beri." 1905. 

6. Ellis, W. G. " Uncnred Rice as a Cause of Beri-beri. British 

Medical Journal. 1909. 

7. Eijkman, C. "Polyneuritis bij Hoenders." Jaarverslag van 

Lab. V. Path. Amat. en Bakt. Batavia, 1896. 



ELECTION OF MEMBEKS. 



The following were duly elected as Fellows of the 
Society : — 
J. H. Dyke Acland, M.R.C.S., Bulawayo. 
Thomas B. Adam, L.R.C.P. and S., West Africa. 
Lieut. -Colonel H. E. Banatvala, I. M.S., Bombay. 
Thomas E. R. Branch, M.B., St. Kitts. 
G. D. H. Carpenter, M.R.C.S., London, W. 
E. A, S. Carrington, Georgetown. 
W. G. 'Clark, F.R.C.S., Bulawayo. 
Major S. Lyle Cummins, R.A.M.C. 
John Bernard Davey, M.B., Nyasaland. 
T. W. F. Gann.'M.B., Corazal, B. Honduras. 
A. Murray Gray, L.R.C.S., Durban. 
Leonard Guthrie, M.D., F.R.C.P., London. 
Philip T. Harper, M.R.C.S., Fiji. 
Karl Heusner, M.D., Behze, B. Honduras. 
J. L. Houlton, M.R.C.S., London, S.W. 
W. R. W. James, L.R.C.P., Liverpool. 
Harry G. Johnston, M.D., Jamaica. 
C. G. KuRiEN, M.B., Travancore. 
Surgeon J. H. Martin, R.N. 
Joseph Clark McPherson, M.B., Antigua. 
Krishnarao Shripat Mhaskar, Bombay. 
David Melville, M.D., Tsolo, Griqualand. 
William Morrison, M.B., West Africa. 



» 



ELECTION OF MEMBERS. 2(59 

Surgeon Parnell, R.N. 

Guy Harcourt Peall, M.B., London, N. 

Captain Joseph F. Siler, Medical Corps, U.S. Anny. 

Surgeon Lewis Smith, R.N. 

H. K. Smyth, M.B., Rhodesia. 

William Taylor, L.R.C.P., New Hebrides. 

F. H. Watling, M.B., Allahabad. 

W. C. Pollard Winter, M.R.C.S., B. Honduras. 



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